I used the red line all the time when I lived in LA. It was crazy to me that so few people who lived there even knew it existed.

At the time, the other two lines were, if I remember correctly, the blue and green lines. Those were much more working class commute type lines that didn't go anywhere particularly interesting, but the red line ran from downtown out through Hollywood, and then on to universal where I could enjoy some of the bars at City Walk without worrying about driving or parking.

Now I live maybe less than five miles from downtown Dallas and I never go there because there's no train and the driving/parking situation is a nightmare.

Clarification: There are trains that go to downtown Dallas. Just not from my neighborhood.

I (US citizen living in Japan for most of a decade) took my wife (only in the US once as an elementary school student and only Honolulu) to DC for the first time a couple of months ago. I was pleasantly surprised. I had ridden DC's subways once or twice on trips there. We were table to do everything we wanted on foot, by bus, and by train. Getting on the train from Dulles, though, we had some only-partly-clothed woman passed out with what I can only assume was a trail of partly-dried piss on the floor by her. Police took her off when we got into the city at some point, but it was a less-than-stellar start. That said, I've seen people puke and piss on trains in Tokyo as well.

Portland is pretty decent too. Not as good as SF, but you can reasonably get around the entire area on public transportation.